CN118306515B - A corrugated surface microstructure with drag reduction function - Google Patents
A corrugated surface microstructure with drag reduction function Download PDFInfo
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- CN118306515B CN118306515B CN202410507175.5A CN202410507175A CN118306515B CN 118306515 B CN118306515 B CN 118306515B CN 202410507175 A CN202410507175 A CN 202410507175A CN 118306515 B CN118306515 B CN 118306515B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING
- B63B1/00—Hydrodynamic or hydrostatic features of hulls or of hydrofoils
- B63B1/32—Other means for varying the inherent hydrodynamic characteristics of hulls
- B63B1/34—Other means for varying the inherent hydrodynamic characteristics of hulls by reducing surface friction
- B63B1/36—Other means for varying the inherent hydrodynamic characteristics of hulls by reducing surface friction using mechanical means
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Abstract
本发明提出了一种波纹形减阻功能表面微结构，属于微结构领域，包括基体上布设有若干凹槽；若干凹槽沿一预设方向布设成行，若干行凹槽沿预设方向的垂直方向布设，凹槽由相对于预设方向的垂直方向镜像对称的两个槽段相连通组成，且组成同一凹槽的两个槽段的相邻端部对接相连通，槽段两端的延伸方向相交叉，位于同一行的相邻两个凹槽的相邻两个槽段交叉设置且相互连通；在基体表面上纵横设置若干凹槽且各凹槽为两个槽段镜像对称组成的结构，由于槽段的两端延伸方向相交叉，使基体表面上形成类似于鱼鳞状的纹路，使形成的纹路结构针对不同流体方向一致具有良好减阻能力。
The present invention proposes a corrugated drag reduction functional surface microstructure, which belongs to the field of microstructures, including a substrate on which a plurality of grooves are arranged; the plurality of grooves are arranged in a row along a preset direction, and the plurality of rows of grooves are arranged in a direction perpendicular to the preset direction, the grooves are composed of two groove segments that are mirror-symmetrical relative to the vertical direction of the preset direction, and the adjacent ends of the two groove segments that constitute the same groove are butt-connected, the extension directions of the two ends of the groove segments intersect, and the adjacent two groove segments of two adjacent grooves in the same row are cross-arranged and interconnected; a plurality of grooves are arranged vertically and horizontally on the substrate surface and each groove is a structure composed of two groove segments that are mirror-symmetrical, and because the extension directions of the two ends of the groove segments intersect, fish scale-like patterns are formed on the substrate surface, so that the formed pattern structure has good drag reduction capability consistent with different fluid directions.
Description
Technical Field
The invention relates to the technical field of surface microstructures, in particular to a corrugated drag reduction function surface microstructure.
Background
The underwater navigation body is used as an important carrier for activities such as ocean exploration, transportation, search and rescue and the like, and plays an important role in ocean economic construction and ocean national defense. The differential pressure resistance and the frictional resistance of the underwater vehicle during traveling can seriously influence the navigation speed, and the energy consumption caused by the differential pressure resistance and the frictional resistance not only restricts the navigation range, but also restricts the loading capacity and the maneuverability of the underwater vehicle. In order to achieve a reduction in the effects of differential pressure drag and frictional drag on the speed of travel of the aircraft, in addition to optimizing the shape of the underwater vehicle, effective control of frictional drag is required.
The method for effectively reducing the surface friction resistance mainly comprises a groove microstructure, a super-hydrophobic micro-nano structure, micro-bubbles and the like. The groove microstructure is a micro topological shape with a characteristic dimension of 1-100 microns and a specific function, such as a micro groove array, a micro pit array, a micro pyramid array structure and the like. The microstructures are generally distributed on a cross-scale mechanical surface of 10-1000 mm, and can change the physical characteristics of part surface friction, lubrication, adhesion, wear resistance, hydrodynamic performance and the like, thereby remarkably improving the functional characteristics of mechanical products and functional parts, including operation efficiency, energy consumption, lubrication and sealing, working noise, material saving and light weight, service life and the like.
Chinese patent CN115258033a discloses a micro-groove bionic drag reduction structure and a preparation method thereof, which combines a groove microstructure and a drag reduction scheme of micro-bubbles. Chinese patent CN116714712B discloses a microstructure of a drag reduction function surface and a molding method thereof, which processes micro grooves on a substrate surface by ultra-precision processing technology. The current micro-groove structure is affected by ultra-precise processing technology, and a simple linear or arc extending structure is adopted, so that the flowing direction of fluid passing through the surface of the micro-groove structure is required to be consistent with the extending direction of the micro-groove structure to exert the drag reduction function, and therefore how to design the grain layout of the micro-structure on the surface of the drag reduction function becomes a problem to be solved urgently.
Disclosure of Invention
In view of this, the present invention provides a corrugated drag reduction function surface microstructure, which is used to solve the problem that the current micro-groove structure is affected by ultra-precise processing technology and mostly adopts a simple linear or arc extending structure, so that the flow direction of the fluid passing through the surface of the micro-groove structure needs to be consistent with the extending direction of the micro-groove structure to exert the drag reduction function, and the layout of the micro-structure on the drag reduction function surface needs to be designed.
The technical scheme is that the corrugated drag reduction function surface microstructure comprises a substrate, a plurality of grooves are distributed on the substrate, wherein the grooves are distributed in rows along a preset direction, the grooves are distributed along the vertical direction of the preset direction, each groove is formed by communicating two groove sections which are in mirror symmetry relative to the vertical direction of the preset direction, adjacent end parts of the two groove sections forming the same groove are communicated in a butt joint mode, extending directions of two ends of the groove sections are intersected, and adjacent two groove sections of the adjacent two grooves located in the same row are intersected and communicated with each other.
On the basis of the technical scheme, the serial numbers of the groove sections in the same row are preferably 1 to n in sequence, the serial numbers of the grooves in the same row are preferably 1 to m in sequence, and the groove sections with even serial numbers and the groove sections with at least one odd serial number in the same row are arranged in a crossing manner and are mutually communicated.
Still more preferably, a gap is reserved between two adjacent grooves, even numbered groove sections positioned in the same row are only arranged in a crossing way with adjacent odd numbered groove sections and are mutually communicated, and the end part of the nth groove section positioned in the same row is in butt joint communication with the end part of the (n+3) th groove section.
Still more preferably, the width of the gap is not greater than the width of the texture formed when the groove segments are laid in the predetermined direction.
Still more preferably, the nth slot segment located in the same row is intersected with the (n+1) th slot segment and the (n+3) th slot segment at the same time, and the end of the nth slot segment in the (m+1) th row is communicated with the (n+2) th slot segment in the (m+1) th row, or the end of the nth slot segment in the (m) th row is communicated with the (n-2) th slot segment in the (m+1) th row.
Still more preferably, even numbered slot segments in the same row are disposed in intersecting relation with and in communication with only adjacent odd numbered slot segments, and the ends of the nth slot segment in the mth row, the ends of the n+3th slot segment in the mth row, the ends of the n+1th slot segment in the m+1th row, and the ends of the n+2th slot segment in the m+1th row are in abutting communication.
On the basis of the technical scheme, preferably, the groove section comprises at least one arc section and at least one straight line section, two groove sections forming the same groove are in butt joint and are communicated through the two arc sections, and the straight line section is communicated with the other end of the arc section.
On the basis of the above technical solution, preferably, the bottom width of the radial cross-sectional shape of the groove is smaller than the top width.
Still more preferably, the included angle between the oblique sides of the groove and the horizontal plane is in the range of 5 degrees to 80 degrees.
Still more preferably, the depth of the grooves is in the range of not more than 1mm.
Compared with the prior art, the corrugated drag reduction function surface microstructure has the following beneficial effects:
(1) According to the invention, the grooves are longitudinally and transversely arranged on the surface of the substrate, and each groove is a structure formed by mirror symmetry of two groove sections, and as the extending directions of the two ends of the groove sections are intersected, fish scale-like lines are formed on the surface of the substrate, so that the formed line structure has good drag reduction capability for different fluid directions.
(2) The groove section of the invention can be composed of an arc section and a straight line section, so that the shape type of a single groove is greatly enlarged, and the groove section of the groove is not limited to a single arc.
(3) The radial section shape of the groove is a structure with a narrow bottom and a wide top, and the processing depth is limited, so that the groove can be processed and manufactured by adopting a forming cutter through a milling method, the forming efficiency of the microstructure can be greatly improved, and the forming process difficulty is reduced.
Drawings
In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a top view of a surface microstructure of the present invention;
FIG. 2 is a top view of another embodiment of a surface microstructure of the present invention;
FIG. 3 is a top view of another embodiment of a surface microstructure of the present invention;
FIG. 4 is a top view of another embodiment of a surface microstructure of the present invention;
FIG. 5 is a top view of another embodiment of a surface microstructure of the present invention;
FIG. 6 is a top view of another embodiment of a surface microstructure of the present invention;
FIG. 7 is a top view of another embodiment of a surface microstructure of the present invention;
FIG. 8 is an enlarged view of FIG. 7A in accordance with the present invention;
FIG. 9 is a side cross-sectional view of a surface microstructure of the present invention;
Fig. 10 is an enlarged view of fig. 9B in accordance with the present invention.
In the figure, 1, a substrate, 101, a groove, 102, a groove section, 103, a gap, 104, an arc section, 105 and a straight line section.
Detailed Description
The following description of the embodiments of the present invention will clearly and fully describe the technical aspects of the embodiments of the present invention, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, are intended to fall within the scope of the present invention.
As shown in FIG. 1, a corrugated drag reducing functional surface microstructure of the present invention comprises a substrate 1.
Wherein, the base body 1 represents a surface with a drag reduction function of a certain requirement device, the base body 1 can enable a metal surface, a plastic surface and the like according to actual requirements, and meanwhile, the surface of the base body 1 is not only limited to a plane, but also can enable a spherical surface, an arc surface and even an irregularly undulating surface. However, for the sake of easy understanding, the surface of the substrate 1 may be regarded as a plane. A plurality of grooves 101 are distributed on the substrate 1, and the grooves 101 form lines on the surface of the substrate 1, so that the surface of the substrate 1 has a drag reduction function.
The grooves 101 are arranged in rows along a preset direction, and the grooves 101 are arranged in a direction perpendicular to the preset direction, so that the grooves 101 form a regular layout structure on the surface of the substrate 1. Meanwhile, the groove 101 is formed by connecting two groove sections 102 which are in mirror symmetry relative to the vertical direction of the preset direction, adjacent ends of the two groove sections 102 which form the same groove 101 are connected in a butt joint mode, the extending directions of the two ends of the groove sections 102 are intersected to enable the groove sections 102 to extend to be similar to an arc-shaped structure, therefore, the shape of a single groove 101 is similar to that of a fish scale or a blade, and when a plurality of grooves 101 are regularly distributed on the surface of the substrate 1, the surface of the substrate 1 is similar to that of a scale layout structure or a texture structure of a shark skin surface forming the body surface of a fish. In addition, two adjacent groove sections 102 of two adjacent grooves 101 positioned in the same row are arranged in a crossing way and are mutually communicated, so that the inner space of each groove 101 is connected into a whole, and the fluid flowing through the surface of the substrate 1 can smoothly flow freely in the layout structure of the grooves 101. Through the combination of the designs, the surface of the matrix 1 has the effect of drag reduction.
In a preferred embodiment shown in fig. 1, the layout of the grooves 101 has various embodiments, and for convenience in describing the layout of the grooves 101, the serial numbers of the groove segments 102 in the same row are sequentially 1 to n, and the serial numbers of the grooves 101 in the rows are sequentially 1 to m. For the different embodiments, it is common that the even numbered slots 102 in the same row are disposed to cross and communicate with the odd numbered slots 102, but the difference is that the even numbered slots 102 cross with several odd numbered slots 102.
For one embodiment represented in fig. 1, with one groove 101 in a certain row as a base point, the groove 101 is formed by mirror symmetry of a groove segment a 1 and a groove segment a 2 in a row b 1, and the groove segment a 2 intersects with a groove segment a 3 of the next groove 101 and a groove segment a 5 of the next groove 101 at the same time, that is, each groove 101 in fig. 1 intersects with its adjacent groove 101 and its adjacent groove 101 at the same time.
In a preferred embodiment shown in fig. 3, one groove 101 is formed by b 1 rows of groove segments a 1 and a 2 mirror symmetry, the groove segment a 2 is intersected only by the groove segment a 3 of the next groove 101, and each groove 101 in fig. 1 is intersected only by its adjacent groove 101.
In a preferred embodiment shown in fig. 4, as another embodiment, a gap 103 is left between two adjacent grooves 101, and meanwhile, in order to enable the fluid flowing through the surface of the substrate 1 to smoothly flow in the grooves 101 in the same row, the even numbered groove segments 102 in the same row are only crossed with and mutually communicated with the adjacent odd numbered groove segments 102, and the end parts of the nth groove segment 102 in the same row are in butt joint communication with the end parts of the n+3th groove segment 102, so that the internal space of the grooves 101 in the same row forms a whole, and at the moment, the point that the end parts of the two groove segments 102 are communicated is just located on the central axis of the groove 101 between the two groove segments.
In a preferred embodiment shown in fig. 2, to reduce the influence of the obstruction that may be caused when the fluid passes through the gap 103, the width of the gap 103 is not greater than the width of the lines formed when the groove segments 102 are arranged along the predetermined direction, so that the fluid can more smoothly flow across the grooves 101 of different rows.
In a preferred embodiment shown in fig. 1, any one groove 101 of each row is intersected with the next two adjacent grooves 101, and the n-th groove 102 of the same row is intersected with and communicated with the n+1th groove 102 and the n+3th groove 102, meanwhile, no gap 103 exists between the grooves 101 of the adjacent rows, so that the end part of the n-th groove 102 of the m-th row is communicated with the n+2th groove 102 of the m+1th row, or the end part of the n-th groove 102 of the m-th row is communicated with the n-2th groove 102 of the m+1th row. Specifically, the groove section a 1 and the groove section a 2 of the row b 1 of the groove 101 are formed in a mirror symmetry, the groove section a 2 and the groove section a 3 of the next groove 101 are intersected with the groove section a 5 of the next groove 101 at the same time, and the end part of the groove section a 2 is communicated with the groove section a 4 of the row b 2. Through the design, the grooves 101 of two adjacent rows are communicated with each other to form a whole, so that the flowing of the fluid in the layout structure of the grooves 101 is facilitated.
In a preferred embodiment shown in fig. 3, any one groove 101 of each row is intersected with only the next adjacent groove 101, so that even numbered groove segments 102 located in the same row are intersected with and communicate with only the adjacent odd numbered groove segments 102. Meanwhile, gaps 103 are not formed between grooves 101 of adjacent rows, and the end part of an nth slot segment 102 of an mth row, the end part of an n+3th slot segment 102 of the mth row, the end part of an n+1th slot segment 102 of an m+1th row and the end part of an n+2th slot segment 102 of the m+1th row are in butt joint communication. Specifically, the groove section a 1 and the groove section a 2 of one groove 101 are formed by mirror symmetry of b 1, the groove section a 2 only crosses the groove section a 3 of the next groove 101, and the end of the groove section a 2 is also in butt joint communication with the groove section a 5 of the next groove 101. Meanwhile, as gaps 103 are not formed between grooves 101 of adjacent rows, the butt joint end of a groove section a 2 and a groove section a 5 is also communicated with the top ends of grooves 101 consisting of a groove section a 3 and a groove section a 4 in b 2 rows, so that the grooves 101 of two adjacent rows are communicated with each other to form a whole, and the flowing of fluid in the layout structure of the grooves 101 is facilitated.
In a preferred embodiment shown in fig. 4, which differs from the previous embodiment in that there are gaps 103 between adjacent rows of grooves 101.
In a preferred embodiment shown in fig. 5, the difference compared to the previous embodiment is that the shape of the groove 101 formed by the two groove segments 102 is not limited to a semi-circular arc, but a semi-elliptical arc can be used, which gives substantially the same drag reducing effect as the semi-circular arc shaped groove 101.
In a preferred embodiment shown in fig. 6, the difference between the previous embodiment is that the shape of the groove 101 formed by two groove segments 102 is not limited to a semicircle, but two circular arc-shaped groove segments 102 are formed by mirror symmetry, and the formed groove 101 is not a continuous arc, and the drag reduction effect is substantially the same as that of the semicircular arc-shaped groove 101.
In a preferred embodiment shown in fig. 7, the difference compared to the previous embodiment is that the shape of the groove 101 formed by the two groove segments 102 is not limited to a semi-circular arc, but a semi-hexagonal shape can be used, but the corners of the hexagon are rounded in order not to hinder the flow of the fluid in the groove 101, and the drag reduction effect is substantially the same as that of the semi-circular arc shaped groove 101.
In a preferred embodiment shown in fig. 8, based on the fact that the drag reduction effect of the surface microstructure of the groove 101 is not greatly affected when the groove 101 adopts different shapes in the above embodiments, it can be inferred that as long as the groove 101 has a mirror-symmetrical structure and the groove segment 102 has an arc-shaped portion, the drag reduction effect of the layout structure of the groove 101 is not greatly adversely affected, and thus the groove segment 102 includes at least one arc segment 104 and at least one straight segment 105.
Taking a semi-hexagonal groove 101 as an example, two groove segments 102 forming the same groove 101 are in butt joint through two arc segments 104 to form a vertex angle of a hexagon, and a straight line segment 105 is a side of the hexagon. In addition, when the grooves 101 are semi-hexagonal, each groove 101 preferably intersects the next two grooves 101 so that the straight sections 105 of each groove 101 are offset to facilitate the flow of fluid over the microstructured surface.
In a preferred embodiment shown in fig. 9, the radial cross-section of the groove 101 is in the shape of an inverted triangle, preferably an inverted isosceles triangle, and the bottom corners of the triangle are rounded, and the shape design enables the groove 101 to be manufactured by conventional milling compared with the conventional micro-groove structure, thereby greatly reducing the difficulty in forming the micro-structure surface. The radial cross-sectional shape of the groove 101 may also be inverted trapezoidal or U-shaped. The radial cross-sectional shape of the groove 101 is related to the shape of the forming tool, and the groove 101 can be easily processed by the forming tool as long as the radial cross-sectional shape is a shape with a narrow bottom and a wide top.
In a preferred embodiment shown in fig. 10, the angle between the oblique sides of the groove 101 and the horizontal plane is in the range of 5 degrees to 80 degrees, and the groove 101 can produce effective drag reduction effect under the angle design, and is also beneficial to being manufactured by conventional milling means.
In a preferred embodiment shown in fig. 10, the depth of the groove 101 is no greater than 1mm, and the groove 101 is designed to provide an effective drag reduction while also being advantageously manufactured by conventional milling means.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the invention.
Claims (9)
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE202011106216U1 (en) * | 2011-09-30 | 2012-01-12 | Helmut Wolfgang Merten | Sliding sports equipment, skis, skids, vehicles o. |
| KR20120095488A (en) * | 2011-02-19 | 2012-08-29 | 이상윤 | Ship propeller with super-hydrophobic surface |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2480701A2 (en) * | 1980-04-17 | 1981-10-23 | Frayssinet Jehan Delpech | CARENE BOWEL DEPRESSOR |
| US10611468B2 (en) * | 2006-09-08 | 2020-04-07 | Steven Sullivan | Method and apparatus for mitigating trailing vortex wakes of lifting or thrust generating bodies |
| KR100981313B1 (en) * | 2008-07-16 | 2010-09-10 | 한국과학기술원 | Patterns with superhydrophobic and superhydrophobic surfaces and methods for forming the same |
| CN102381435B (en) * | 2011-09-06 | 2013-07-17 | 山东理工大学 | High-fidelity shark-imitating anti-drag structure capable of slowly releasing drag reducer instantly and manufacturing method thereof |
| US8632327B2 (en) * | 2011-11-28 | 2014-01-21 | General Electric Company | Apparatus to apply a variable surface texture on an airfoil |
| CN116552696B (en) * | 2023-05-18 | 2025-10-14 | 南京理工大学 | An electromagnetic groove composite drag reduction device |
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20120095488A (en) * | 2011-02-19 | 2012-08-29 | 이상윤 | Ship propeller with super-hydrophobic surface |
| DE202011106216U1 (en) * | 2011-09-30 | 2012-01-12 | Helmut Wolfgang Merten | Sliding sports equipment, skis, skids, vehicles o. |
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